Wyeth and Progenics Pharmaceuticals Announce Submission of Marketing Application in Europe for the Subcutaneous Formulation of Methylnaltrexone

Application for the Treatment of Opioid-Induced Constipation in Patients with Advanced Illness.

Collegeville, Pa. & Tarrytown, N.Y.,— Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE), and Progenics Pharmaceuticals, Inc. (NASDAQ: PGNX) announced today that Wyeth has submitted a marketing application to the European Medicines Agency (EMEA) for a subcutaneous formulation of methylnaltrexone for the treatment of opioid-induced constipation (OIC) in patients with advanced illness. Methylnaltrexone is a peripherally acting opioid-receptor antagonist that is designed to treat OIC without interfering with pain relief. A New Drug Application for the same formulation of methylnaltrexone was submitted by Progenics to the U.S. Food and Drug Administration on March 30, 2007. “Methylnaltrexone has the potential to address a major gastrointestinal side effect of opioid therapy. Therefore, this EMEA application is an important development and a major milestone,” says Gary L. Stiles, M.D., Executive Vice President, Chief Medical Officer, Wyeth Pharmaceuticals.

The marketing application is based on data from two Phase 3 studies that evaluated the safety and efficacy of the subcutaneous formulation of methylnaltrexone in the treatment of OIC in patients with advanced illness. All of the primary efficacy endpoints of the studies were positive and statistically significant, and the therapy generally was well-tolerated.

Opioid analgesics commonly are prescribed to manage pain in patients with advanced illness. Some experts have stated that constipation occurs in nearly all patients on opioid therapy. There currently is no approved medication that specifically targets the underlying cause of OIC to relieve constipation in this patient population.

Opioids provide pain relief by interacting with specific opioid receptors located in the central nervous system (CNS) — the brain and the vertebral column. However, opioids also interact with the receptors outside the CNS, such as those affecting the gastrointestinal (GI) tract, altering intestinal motility and resulting in constipation that can be debilitating. Patients suffering from OIC may experience dry, hard stools; straining during evacuation; and incomplete and infrequent evacuation. Other symptoms of OIC can include nausea, vomiting and abdominal discomfort or pain. If left untreated or unresolved, OIC can lead to fecal impaction that may require manual removal.

“This milestone represents our commitment to patients who suffer from the debilitating effects of OIC and offers them hope,” says Paul J. Maddon, M.D., Ph.D., Progenics’ Founder, Chief Executive Officer and Chief Science Officer. “Progenics filed a New Drug Application for this formulation of methylnaltrexone with the U.S. Food and Drug Administration in March of this year. The progress we have made with submissions to U.S. and European Union regulatory agencies underscores the strength of the collaboration between Progenics and Wyeth, and of our joint dedication to serving the needs of these seriously ill patients.”

Submission of this EMEA application will result in a $4 million milestone payment being made to Progenics Pharmaceuticals. In December of 2005, Wyeth and Progenics entered into an exclusive, worldwide agreement for the joint development and commercialization of methylnaltrexone for the treatment of opioid-induced side effects, including constipation and post-operative ileus (POI), a prolonged dysfunction of the GI tract following surgery. Under the terms of the collaboration, Wyeth received worldwide rights to methylnaltrexone, and Progenics retained an option to co-promote the product in the United States. The companies are collaborating on worldwide development. The transaction included an upfront payment of $60 million to Progenics with as much as an additional $356.5 million payable upon achievement of certain milestones. Wyeth has agreed to pay Progenics royalties on worldwide sales and co-promotion fees within the United States. Additionally, Wyeth is responsible for all ongoing and future development and commercialization costs.

About Methylnaltrexone
Methylnaltrexone is an investigational drug that is being studied as a treatment for the peripheral side effects of opioid analgesics. It is designed to mitigate the effect of opioids on peripheral receptors without interfering with central nervous system pain relief. Methylnaltrexone is being developed in subcutaneous and oral forms to treat opioid-induced constipation and an intravenous form for POI.